Pneumatic tire



May 31, 1932- L.. JONES 1,860,362

PNEUMATICI TIRE Filed Deo. 23. 1929 Tim-L u Ti'' INVENTOR Lesfev L. Jones ATTQRNEYS PatentedV May 3l, 1932 UNITED STATES PATENT OFFICE LESTER L. v.'.l'olll'llla ORADELI, NEW JERSEY PNEUMATICI TIRE Application mea December 2a, 1929. serial No. 416,001.

This invention relates to .Ipneumatic tires, and more particularly to ba loon ti-res and a safety buffer therefor. v

The pneumatic tire most inA use to-day 1s B the low pressure, or so-called balloon tire.` lVhen such tires are deflated, due to a blowout or puncture, the vehicle tilts sharply because 4of the resulting decrease in effectiveA diameter ofthe wheel. 'The deflated shoe is l extremely loose on the wheel rim, andas the;

rate of speed. The danger is particularlyv pronouncedwhen one of the front Wheels is involved, because of the powerfultendency to swerve in direction createdby theforegoing factors, particularlythe extreme difference in front wheel diameters.

Even if the vehicle is running at a relatively slow rate of speed, considerable inconvenience results from the fact that on account of the tendency to gather or bunch in front of the Wheel, and because of the relatively thin walls of a low pressure shoe, such ashoe cannot 'be run fiat for even a short distance without seriously injuring the shoe, Thef urgent necessity of immediately changing the tire is frequently embarrassing when the puncture occursfon a narrow road or a narrow bridge, or lWhen the traveler would like to continue to a service station to have the shoe changed. i

In general, the object of the present in` has any proposedsafety device proved comvention is to overcome the various foregoing difficulties which arise With Ipneumatic tires, by the provision of a safetyrim or buffer.

It has previously been suggested to employ such arrangements utilizing aninflated tube additional to the usual inner tube, but these suffer from the disadvantage that when the shoe picks up a -nail or the like, it ordinarily will puncture the additional tube 'when the latter takes the loadof 'the vehicle. lIn accordance with my`invention, a safety rim 5 or buffer made of solid rubber and fabric is for example,`

employed, thereby obviating the difficulties attendant upon the attempted use of a pneumatic buffer.

It has also ,beenisuggested to form the shoe 'With an inwardly directed ring for taking. the Weight of the vehicle in the event of deflation,

' but such an arrangement necessitates a special shoe of complex construction, and robs the'shoe of its "desired flexibility. Such a shoe is ineicient because the fleXure in' ordinary use of the 'relativel thick structure would' Alead to large mec anical h steresis losses, and the tire would heat up ba ly when `runnlng. n

It has further been proposed to form a safety ,rim onthe interior of the inner tube.y

This di'sregards the fact that the only practi cal form of the automobile pneumatic tire is ythat in which the air tube is a separableele-` ment from the shoe, and that the conditions for manufacture of erfectly air-tight and permanently flexible inner tubes are very se- Vere and do not permit of such additions being made to the tube structure. In the practice of my invention, the inner tube may be a conventional innertu-be, and even if specially formed for use with my safety buffer, the inner tube is conventional in the sense that itmaybe made of thin flexible high grade rubber of' substantially Vuniform4 thickness, and be provided with a valve stemof the conventional type.

'Numerous other proposals havebeen made, but in -each casethe suggested improvement necessitates considerable change in the constructionofthe shoe or/and the inner tube or/and the Wheel upon which the tire is to be mounted, and in no case of'which I am aware mercia ly successful.4

Accordingly, one rimary object of my inventionv resides in th) i rim or buffer for use with pneumaticfand particularly with balloon tires, which not reduce the resiliency,- efficiency, .and shock absorbing properties of the tire.. This object I fulfill yby substituting for the usual 'protective strip or flap which is placedl around the e provision of.a safety vWill'n'ot l necessitate the use of a special shoe, norLthe ,use of' a special innertube, and which Will that is,-

1lil

inner periphery of the 'shoe in order to protect the inner tube from direct contact with the wheel rim, a safet rim or internal bader comprising a solid ru ber and fabric ring of 'generally wedge shaped cross-section. This -onl partiallyuntil'it reaches the outer p'e-A rip ery o f the buffer, thereby preventing the undesired extreme reduction in wheel diameter with its consequent danger. j

A further object of fthe present invention is to overcome the tendency ofthe lshoe to .leave the Wheel rim when deflated, and with this in view .the base portion of the internal buffer is so shaped that the central portion thereof rests directly on the wheel rim while to hold the shoe on the wheel rim.V

3fabric. These layers of fabric are when accelerating or applied to the wheels'. o

the edge portions thereof rest against the inner surface of the beads of the shoe in order :Another object of the present invention is to prevent injury to the inner tube near the valve stem when runnin on the safety rim, and this'is accomplishe4 by providing the safety rim or internal buffer with a recess for protectively receiving the inner end of the valve stem.

A further object ofthe present invention is to provide against the'rotational -stre'ss -which may be' set up between the wheel and the buffer when the wheel is rotated by the en 'ne or is held back by the brake. This object I fulfill by providing the buffer with y spaced metallic inserts and cooperating locking means for anchoring the buffon to the wheelv rim.` These inserts are preferably so shaped that the locking action helpsfanchor the shoe onto `the rim, as well as'takes' drivin or braking stress- I'urther features-of my invention deal with the texture or nature vof yreinforcement of the safety rim or internal buffer.:` The base I portion ofthe buffer is'fstrongljvreinforced referably "made wi cumferential `'.-direction irr'vaorderrto prevent expansion of the buffer-bildercentrifugal force, and .to prevent longitudinalcreeping "This reinforcement `the base portion .of-fthei buier'servest'o .strengthen it foritsjfunction of holdingl the y beads of theshoe against the wheel rim,- and furtherserves as?4 secure medium in which .the aforementioned metallic'inserts may be imbedded, T his reinforcement: also serves to prevent anundesiredchan'ge in the shapeof the base portionof the buffer when it is loaded with the weight of the vehicle.

v.A further object of the present mvention `l`tively 'strands should preferably be made so weak thl strong threads in #t er cir-"f decelerating force is p,y

1,seo,sea

is to make the safety rim or buffer of minimum weight, minimum cross-section, and maxlmumresiliency. This is done, generally, b taking advantage of-the fact that the sa et rim does not normally support a load,\`an its period of use ordinarily is relatively infrequent and relatively short in duration, and therefore placing all sections of theA rubber in the safety rim except the base portion previously described,under a marimum and uniformly high distortion when loaded. Structurally, this is accomplished by building up the buffer of layers of rubber cemented together with reinforcing strips of fabric therebetween. The threads of the fabric are Inaderelatively sparse and Weak in a circumferential direction, but i relatively strong in a transverse direction. The spacing of the reinforcing strips is made relatively great. In this way each of the layers ma be subjected to considerable distortion an y loading, while the strong transverse reinforcement causes the inner layers ito be subjected to loading similar to that of the outer layers of rubber.

If the tire assembly so far described is run in a defiated condition for a considerable wheel, and a constant slippage must take place between the. buffer and fthe shoe in order to relieve this accumulation of shoe material.' n

This diflicultl is partially overcome by the structure already described, in which the circumferential reinforcement ofthe outer portionnof the safety rim orbuffer is made relaweak. In fact, the circumferential as to easily break when the load is placed on thesafety'rim, for this increases the circumferential resiliency of the safety rim. I have y 1a plurality "of `closely spaced layers of\fo u ndy that if the outer layers of rubber on the 'buifer lbe permitted', to expand circum- "ferentially when placed under compression the' angular velocity of the wheel is reduced or,- in other words, the wheel behaves as though its diameter were-commensurate with `a..cireu mference based upon thel expanded segment of circumference uponi which the wheel rests. The circumferential expansion of the .bufferl in effect elongates the periphery thereof at the portion which is -in contact with the deflated shoe, and in this manner the angular-velocity of the wheel may be reduced-to accurately. correspond with-that of the deflated shoe'.

Another manner in which this desired result. may be obtained is totransversely slot the peripheryiof the buffer.. I n thismanner the tread of the buffer consists of separate rectangles which are each quite iexible in a circumferential direction, and which may yield circumferentially independently of the adjacent sections of the periphery of the buffer. Without` these transverse slotsl the circumferential tension in the rubber supporting .the vehicle weight might be communicated to the new rubber coming into compression as the wheel'rotates, and 1n` this manner the circumferential tension might be cumulatively increased until slippage oc'- curred. To the accomplishment of the foregoing andsuch `other objects as will hereinafter appear, my inventionconsists in the elements and their relation one to the'other as hereinafter are more particularly described in the specification and sought to be defined in the claims. The specification is accompanied by drawings in which:

Fig. 1 is a section through a tire assembly embodying my invention; 1

Flg'. 2 is a section taken through the tire assembly at the valve stem;

Fig. 3 is a partially sectioned `elevation 'and a wheel and tire assembly embodying vthe invention; and l Flg. 4 1s a fragmentary a safety rim or buffer under compression. Referring to the drawings, the Atire assemf bly consists of an outer shoe 2, .an inner lhigh grade 'thickness and great iiexibility/ Irl/the caseof inner tubes of more expensive manufacture which are tailored or /preformed to the desired annular shape, the tubes intended for use with theV present invention may be pre- -formed with a cross-'sectional shape corresponding to that shown in'Fig. 1 of the drawings, that is, the annular indentation caused by the' b uifer 6 may be allowed for in advance. Even such a lshaped innerltube I consider to be a conventional innei` tube in every material respect, because itlis' designed and may be manufactured witha special view to being air-tight and flexible; 4 is provided with a valve stem 12 o f the of substantially uniform thickness, except for such strengthening as maybe customary as,for example, the thickened area 14 adjasection through long life, and great- The inner tube.

cent the point of attachment-of the valver stem 12 to the inner t'ube.

The safety rim or internal buffer 6 is placed inside of the beads 16 of the shoe and between the inner tube 4 and the wheel rim 8, and serves to replace the strip or fiap now used in the same positionv to prevent the inner tube from pinching between the edges or beadsA of the shoe 16 and the rim 8, and to` prevent chafing of the inner tube against therim and exposure to rust on the rim, and vso on. The buffer is 18 for the valve Vstem'12, andthe periphery is recessed as at 20 in order to form a pro# tective seat for the'innr ed 'of the valve stem; If the recess 2O I full weight of the vehicle would be applied to the inner endv of the valve' stem when the shoe is deflated, and this would crush or shear the valvestemiangeandthe section of rubber 14, and so'ruin the inner tube. As here. disclosed, the buffer `is preferably a closed annular rim, but it will be understood that if desired it may be made in the form of a strip `having overlapping ends of reduced crosssection, preferably located a't the Valve stem aperture 18, in still closer resemblance t0 the usual protective flap now used. v

As Iis evident from the drawings, the safety buffer 6 comprises a base portion 22, and an outer portion 24. The base portion 22 is so shaped that the central portion 26 thereof rests upon the wheel 'rim 8, while the edge portions 28 thereof rest against 'face .of` the beads or edge walls 16 of the provided with an aperture. I

werefnot provlded the the inner sur shoe 2. In this manner the buii'er tendsto hold the shoe 2 on the wheel rim 8 not only when the tube is inflated but also when it is deflated. The base portion l22 is reinforced with a plurality of closely spaced la ers of fabric, and these serveto strengthen t e base j portion so` that it will retain the desired sha e even when the buffer 6-i's loaded witii ,the weight of the vehicle. -The reinforcing layers are preferably made with strong circumferential threads lin order to give the buiier` considerable circumferential strength .so as to'prevent its expansion under centrifugalforce when rotating at high speeds, and to prevent longitudinal' creeping when accelerating or decelerating force is `applied to the wheel 10.

To properly hold the shoe on the rim when the tire is `deiated is not a simple problem. When a tire which is not rotating becomes fiat it will be found that the bend inward and depart from the edges -'or flanges of the wheel rim at portion 4ofthe shoe upon which the vehicle is resting. When the wheel is rotating this condition becomes rapidly. aggravatedL'be-- usual type, and the tube 1s made of rubber either side of vthe wallsof the shoe cause the portion of the'shoe having .thein-f ing of `the shoe which theshoe, which problem is considersdilatr.

sufliciently wide t'o' extend along theinner It should be noted that in the-safety buffer 6 of my invention th'e base vportion 22 is edge wal-ls of the shoe 2 oints opposite difference in radius of the rim and i.

felloe. These recesses may beu-"concealed, by

that the rim 8, instead of being demountable,

may be a part of a completely demountable wheel, such as awire wheel, disc wheel, or the.

like, or need not be demountable.

The outer portion 24 of the safety buffer is designed to be' of minimum weight and minimum cross-section :fory Vits purpose. The buiier normally supportsno load except the [aid pressure, and ordinarily-undergoes no deation. "Its use under load is limited .to a

the ed es 9 of the flanges of t e wheel rim 8. relatively short period of time, -and onl at With t is arran ement` direct pressure d ue to' theweight of t e vehicle on the periphery of the buffer 6 is transmitted to the bottom or edge walls of the shoe 2 and holds them securely against the rim 8.all` the way out to the edges .9 thereof. Initial bending in-v ward of the Walls of the shoe away from the f a'nges of the wheel rim is prevented andy effective by bend;-

ing in of the shoe walls is also prevented, so that one .source-of bunching of the shoe and bumping of the wheel, with its concomitant Wear of the shoe and its tendency to cause the shoe to leave the rim is'entirelyfovercoine.

AThis advantage may be made still more 4the use of metallic anchoring insertsBO. The safety rim or buier is ref-vl erably provided with a plurality of suc inconsequently cumulative departure or .serts spacedrequally around the rim. In

ythe present case six areprovided, and ordinaril this number will suilcel These inserts are threaded to receive bolts 32, which may be threaded into the inserts 30 through aperv tures 3l provided in the Wheel rim 8. The

which therubber isvulcanized The wings apertures may be and preferably-aremade in the form of longitudinally directedlslots, so as towallow for slight irregularities in the location of the metallic'inserts'i The i-netallic inserts should" .include transversely"extend-'w' ing wings34-of generous dimension,and may desirablybe providedwith apertures 35, thru 34, p errnit the,y locking bitsff 'E12-to"n .draw Athe the beads loof the shoe, 1thereby" securely' vlas buffer.

anchoring't'he'fshoe to the rim even when deserts 30 in the safety rini is'strengthened by the `fabric reinforcementoffthe base portion braking forces serve to take the drivingior the safety when the .vehicle ris running on The strips are" rf'ess of the rubber layers is properly the buierldirectlyagainst "-y,

relatively infrequent occasions;` Theru ber of the buier may, therefore,

or buiier is made up. of alternate layersofrubber and fabric. The fabric may be a canvas or a cord fabric, and is preferably of suiiciently open weave to perlnlt an intimate' bond between the rubber and the canvas, and between the rubber layerson either side of each strip of canvas. The weave is one which be subjected to maximum distortion to an lextent which', if l results in considerablestrength transversely.

of the safet parallel t0 t that the stronger to the edges of the strips. trated in Fig. 4,these transverse threads'dis tribute the loa-d upon the buffer; causin the innerl'ayers 42 to be distorted or'bu ged, the same as the outer layers 44. The thickrelated to the width or axial dimension of t e layers to vpermit of the desired distortion or bulge. .Inthis manner the buifer may have the desired resiliency which would be lost if the rubber layers vwere made too thin. On the other hand, if these layers are made too thick threads are perpendicular andthe bulge becomes too pronounced theV rim, that is, inth'e direction e' axis ofrotation of the wheel. therefore preferablycut so As is best illusins entirebody oirubberis not stresseduniformandthe ratio of load carrying capacity to the total Weight of rubber in the sa c ty rI he circumferential strands of the fabric inthe outer portion 24 .of the buffer are preferabl support the 'transverse' threads, and Ato space them while the fabrieis being-vulcanized into the buffer. .The circumferential threads.

widely spaced and. .relatively 0f the safety-P1111, andi-ht? locking bolts 32 'fvea'kT ieir primar-y function is merely to ias *of the buffer; 'I

The circumferential threadsv maybe made particularly weak in the outer layers of fabric, and the number of layers of fabric, beginning at the periphery of the safety rnn and going toward the base portlon of the same, which are made with circumferential threads of negligible strength helps determine the amount of circumferential expansion which the safety rim will experience when loaded. This should preferably be adjusted to cause the angular velocity of the wheel to correspond as accurately as possible to theangular velocity of the deflated shoe. For `example, if the shoe is of relatively large crosssectionI compared with the wheel diameter, thereby-causing considerable difference in the angular velocit of the wheelwhen deflated, I make the sa ety rim highly expansive in the Acircumferential direction by providing extremely Weak circumferential threads in a plurality of the outer layers-of reinforcing fabric. On the other hand, if the cross-section of the tire'is small, relative to the wheel diameter, only the outermost layer of reinforcing fabric may be made with no clrcumferentialy reinforcement. In this manner when the buffer takes the vehicle load the outer portion of the saine for a given radial angle expands circumferentially to a length equal to that of the periphery of the shoe over the same radial angle.

As a final precaution intended to obviate wear of the .inner tube, when the tire assembly -is run in the de iiated condition the periphery of the safety buffer 6 may be trans-` versely slottedvv as at 50. 'These slots cause the buffer to have a tread of its own, consisting of rectangular areas of rubber separated by relatively large expansion spaces. The curvature of the edges of the slots and the `width of the slots l are made suiiiciently great to prevent the inner tube 4 from being too sharply bent andfrom being pinched between adjacentsegments of the tread of the buffer.

This slotted construction prevents gathering or bunching of the shoe in front of the wheel, and relieves the accumulation of the material of the shoe which might otherwise take placeH This phenomenon may be explained on the theory that each of the independent tread areas may be separately distorted, and the necessary slippage between the safety rim and the shoe maybe allowed for between the successive tread areas. Each tread. area may expand circumferentially independently of the adjacent tread areas. The

circumferential displacement of the rubber under compression therefor cannot be communicatedto the tread areas next coming into compression, and no cumulative distortion of the rubber of the safety rim can therefore take place. v

. The Vdepth of the slots 350 is preferably made less than the thickness of the outermost layer of rubber in order-notte cut throughA theoutermost layer of fabric, but this is not a necessary condition for, explained, the transverse threads of the outermost layer of fabric are the only threads which are usefullyemployed.

From the foregoing description, the manner of constructing and using, and the many advantages of my safety rim or internal buffer, will be apparent. The shoe and inner tube are of ordinary construction, and therefore will possess all of the operating advantages so far developed in this art. The wheel rim wil1,. if no metallic inserts are used in the safety buffer, also be of ordinary construction, and if the metallic inserts are used in the buffer as preferred, the wheel rim will differ from the ordinary rim only in being as was previouslyv provided with a plurality of spaced aperv tures with which the locking means may cooperate. The safety rim or buffer itself is of relatively economical con-struction, particularly if it is kept in mind that by its use the protective flap or strip ordinarily needed may be dispensed with. The buffer does not interfere with the ordinary shock absorbing action of the pneumatic tire, but in the .event of a. puncture or blow-out, prevents dangerous reduction in wheel diameter, and prevents bunching offthe shoe in frontof the wheel rim, and prevents the shoe from leavin the Wheel rim, all of which factors make 1t possible to run on the buffer a reasonable distance to find a convenient location or, if desired, a service station to make the necessary repair. In a severe emergency, as in the case of a very badly torn shoe and no spare tire available, the shoe may be ripped from the wheel rim, and the safety rim will alone be useful as a solid tire for a short distance. When the shoe is deated the wheel is nevertheless capableof accommodating driving or braking forces, and the inner end of the valve stem is protected against injury. Wear of the deflated inner tube, and bunching of the collapsed shoe in front Iof the bader, are prevented not only bythe large diameter of the buffer relative to that of the wheel rim, but also by the precautions permitting circumferential expansion of the buffer previously described.v

- It will be apparent that while Iha'vefshownf125 departing from the spirit offri@ invention, v

defined in theifollowing claims.

prising a continuous ring made of solid rubber and fabric and having a generally wedgeshaped cross section the base portion of which is broad and so shaped that the central portion thereof will rest directly on a conventional wheel rim while the edge portions thereof will rest against a Wide portion of the inner surface ofthe beads of a conven-V tional shoe in order to hold the shoe on the Wheel rim, and the'outer portion of which extends radially beyond the wheel rim flanges and is not rein-forced ina circumferential direction, and is generally designed to permit of a large amount of circumferential ex pansion. 2. A safety buffer for pneumatic tires comprising a continuous ring made of solid rubber and fabric and having shaped cross section the base portion of which is broad and strongly reinforced b a plurality of closely spaced layers of fabric and shaped so that the central portion thereof will rest directly'on a conventional wheel rim While the edge portions thereof will rest against va Wide portion of the inner surface o the beads of a conventional shoe in order to hold the shoe on the wheel rim, and the outer portion of which extends radially beyond the wheel rim flanges and is strongly reinforced, sol ily 1n a transverse direction by widely spaced layers of fabric. i

3. A safety buffer for conventional pneumatic'. balloon tires comprising a continuous ring made of solid rubber and fabric and having a generally wedge-shaped cross sec-y tion the base portiorrof which is broad and strongly reinforced by a plurality of closely s aced layers of fabric and shaped so that t e central portion thereof will rest directon the Wheel 1 thereof will rest against a wide portion of ly. reinforced by a lthe inner surface of the beads of the shoe in order to hold the shoe on the Wheel rim, the outer portion of the buffer extending radially beyond the wheel rim flanges and being strongly remforced solely in a trans-f verse direction. by widely spaced layers of fabric, and the buffer being'provided with 'an aperture for thevalve stem of an inner tube and avrecess localized at the aperture for protectively receiving the inner end o the valve stem.

4. A safety buffer'for conventional pneumatic balloon tires comprisin a continuous ring made of solid rubber and abrio and having/a generally Wedge-shaped cross section the base portion of which is broad and strongplurality of closely spaced layers of fabric and shaped so that the central portion thereof will rest directly on the Wheel rim while the edge portions thereof `will rest against a Wide portion' of the inner surface of the beads of the shoe in order to a generally wedge- -most layer of rubberv .slotted around the periphery of the'buffer, a

rim while the edge portions.

f strongly rein the inner surface of the Wheel rim flanges and being strongly reinforced solely in a transverse direction by Widely spaced layers of fabric, the outermost layer of -rubber being transversely slotted around the periphery of the buffer, and the buffer being provided' with an aperture for the Valve stem of` an inner tube and a recess localized at the aperture for protectively receiving the inner end of the ,valve stem.

5. A safety buffer for tires comprisinga continuous ringof solid rubber and fabric and having a 4generally 'wedge-shaped cross section the base portion of whichis'previdedwith spaced metallic in- .serts and cooperative locking means for anchoring the buffer t0 a wheel rim, the outer p ortion of the buffer extending radially be yond the Wheel rim flanges and being strongy rein-forced solely in a transverse direction by widely spaced layers of fabric, the outerbeing transversely and the buifer being provided with an aperture for thevalve stem of aninner tube and a recess localized at the aperture for protectively receiving the inner end of the valve stem.

6. A' safety-buffer for conventional pneumatic balloon tires comprisin a continuous ring made of solid rubber and abrio and hav- :pneumatic balloon ing a generally Wedge-shaped cross section the outer portion of which extends radially beyond the wheelrim flanges andthe base `portion of which is broad and strongly reinforced by a lurality of closely spaced layers of fabric an shaped so that the central portion thereof will rest'. directly on the wheel rim while the edge portions thereof will rest against a Wide portion of the inner surface of thebeads of the shoe in order to hold the shoe on the Wheel rim, andis provided with spaced metallic inserts held in thev aforeof fabric and cooperating locksaid layers for anchoring the buer t'o the ing means wheel rim.

7 A safety buffer for conventional pneumatic balloon tires com rising a continuous ring made of .solid ruliber and fabric and having ,a generally ,Wedge-shaped cross sec. tion the base ortion of which is broad and orced by a plurality of closely spaced layers of fabric and shaped sothat the central portion thereof, will rest directly on the Wheel rim While the edge portions thereof will rest against a Wide portion of the beads of the shoel in order to hold the shoe on the wheel rim. and is provided with spaced metallic inserts held in the aforesaid layers of fabric and cooperating locking means for anchoring the buffer to the Wheel rim, the outer portion of the -buffer extending radially beyond the wheel rim flanges and being strongly'reinforced solely in a transverse direction by Widely spaced layers of fabric, and thebufer being provided With an aperture for the valve stem of an inner tube and a recess localized at the aperture for protectvely receiving the inner end of the valve stein.

8. An automobile Wheel assembly comprising a conventional shoe, an air-tight inner tube made yof flexible rubberof uniform ,10 ,thickness and provided with a valve stem of the conventional type, a solid rubber and fabric safety buffer in the form of a continuous ring of generally Wedge-shaped cross section replacing the usual protective flap, and a Wheel rim of conventional shape provided with a valve stem aperture, said buffer comprising an outerI portion which extends radially beyond the wheel rim flanges, and a base portion which is broad and so shaped that the central portion thereof restsdirect ly on the wheel rim while 'the edge portions rest on a wide portion of theinner surface of the beads of-the shoe extending to points opposite the anges ofthe rim so that pressure on the buffer is applied directly to the beads and the flanges in order to hold theshoe on theriin. 9. An automobile wheel assembly comprising a conventional shoe, an air-tight inner tube `made of flexible rubber of uniform thickness and provided with a valve stem of the conventional type, a solid rubber and fabric safety buffer in, the form of a continuous ring of generally Wedge-shaped cross section replacing the usual protective ap, and a Wheel rim of conventional shape provided With a valve stem aperture, said buifer comprising a base portion which is broad and strongly reinforced by a plurality' of closely spaced layers of fabric and shaped so that'the central portion thereof, rests'idirectly on the Wheel rim while the edge portions reston the inner surface of the beads of the shoe in order to hold the shoe on the rim, the outer portion of the buffer 'extending radially beyond the Wheel rim anges and being strongly reinforced solely in a transverse direction by widely spaced layers of fabric, the outermost layer of rubber being transversely slotted around its periphery, and the buffer being provided with an aperture for the valve stem of the inner tube and a recess localized at the aperture for protectively receiving the inner end of the valve stem.

10. An automobile Wheel assembly comprising a balloon tire shoe, an air-tight inner tube made. of flexible rubber of uniform thickness and provided with a valve stem of the conventional type, a solid rubber and fabric safety buffer in the form of a continuous ring of generally Wedge-'shaped cross section replacing the usual protective flap, and a wheel rim provided with a valve stem aperture and a plurality of additional slots spaced around thel Ap eriphery of the rim, said buffer comprismg" an .outer portion which extends vradially beyond the Wheel rim flanges and acbase portion which is broad and strongly reinforced by a plurality of closely spaced layers of fabric, and which is ,so Shaped that the central portion thereof rests directly on the-,Wheel rim while the edge portions rest on a 'wide portion df the inner surs face ofthe beads of theshoe in order to hold the shoe on vthe wheel rin'r, and which has spaced metallic inser'ts held in the aforesaid layers of'fabric and locking meanscooperating therewith and .with the slots in the wheel rim for anchoring the buffer thereto, and the buffer being provided lwith an aperture 'for the valve stem of the inner tube and a recess localized at the aperture for protectively receivin the inner end of the valve stem.

v 11. safety buffer for pneumatic tires comprising a solid continuous ring made of rubber and fabric to be placed between the inner tube and thewheel rim of a pneumatic tire assembly, said buffer extending radially outward beyond the flanges of thewheel rim andthe periphery of said buffer being transversely slotted with a large number of small slots to form a substantially continuous tread which is highly resilient in a circumferential direction.

l2. A safety buffer for pneumatic tires comprising a solid continuous ring made of rubber and fabric to be placed between the inner tube land the wheel rim of a lpneumatic tire assembly, said buffer extending radially outward beyond the flanges of the wheel rim and comprising `a base portion, an intermediate portion, and a y peripheral portion being slotted with a large number of small slots to form a-substantially continuous tread which is `highly resilient in a circumferential direction, the intermediate n portion being reinforced solely againsttran'sverse expansion, and the base portion being reinforced against circumferential expansion. 13. A safety buffer for pneumatic/tires comprising a solid ring made of rubber and fabric having a. base portion andan outer portion, said outer portion extending radially beyond the Wheel rim Harige and comprising alternate layers of rubber and fabric, the strong threads of the fabric extending transversely of the the compressibility of each of the layers of rubber, and the layers lof rubber having' a relative thickness predetermined to cause approximately equalized maximum distortion in each layer thereof when the bu'er is loaded.

14. A safetybufi'er for `pneumatic tires comprising a solid rubber and fabric continuous ring of generally wedge-shaped cross perlpheral portion, the.

buffer in order to limit section having a base portion l and an 'outer po'rtion, said base portion being strongly reinforced in a circumferential direction by a plurality of closely spacedlayers of fabric, and said outer portion extending radially beyond the wheel rim {ianges and comprising alternate layers of rubber and fabric, a plurality of the layers of fabric in the outer' portion having 'diiferentstrengths in a circumferential direction, and the circumferential strength of the outermost layer of fabric be-A ing negligible.

10' 15. An automobile wheel assembly comprising a shoe, an air-tight inner tube, a wheel rim, a safety buffer including a' continuous ring of solid rubber and fabric of generally wedge-shaped cross section to be placed between the inner tube and the wheel rim, said buffer having a base portion strongly reinforced in a circumferential direction by a plurality of closely spaced layers of fabric, and

v'an outer' portion which extends radially beyond the wheel rim flanges and is sopropolu tioned that when taking the vehicle load it expands circumferentially to a length substantially equal to that of the periphery of the shoe for a given radial angle'.

Signed at New -York in the county yof New York andI State of NewYork this 11th day of December A. D. 1929. A v

` LESTER L. JONES. 

